Process for heating retorts.



F. T. BEERS PROCESS FOR HEATlNG RETORTS.

APPLICATION FILED NOV. 15, 1913.

1 140,35 1 Patented May 25, 1915..

0/.) v V gwwmtoz WKWMM UNITED. sfrrirns PATENT OFFICE,

FRANK TROXELL BEERS, OF BARKSDALE, WISCONSIN, ASSIGNOR TO I. DU PONT DE NEMOURS POWDER COMPANY, OF WILMINGTON, DELAWARE, A CORPORATION OF NEW JERSEY.

PROCESS FOR HEATING .RETORTS.

Specification of Letters Patent.

Application filed November 15, 1913. Serial No. 801,175.

To all whom it may concern Be it known that I, FRANK TROXELL Beans, of Barksdale, in the county of Bayfield, and in the State oflVisconsin, have invented a certain new and useful Improvement in Processes for Heating Retorts, and

do hereby declare that the following is a full, clear, and exact description thereof.

My invention relates to a process for heat ing retorts of all kinds, but it is applicable especially for the heating of retorts used for the distillation of nitric acid. 1,

My invention is particularly applicable to the heating of retorts containing sodium the process of nitric acid fromsodiuni nitrate and sulfuric acid by heating the same in cast iron retorts set in brickwork and fired directly from a coal or oil fire. These retorts have, however, been increasing in size until they have reached, in some instances, a capacity of 20,000 pounds, and as a result considerable diificulty has been experienced from the cracking of the retorts due to uneven heating. None of the plans previously proposed to avoid this uneven heating and to avoid the strain produced in the comparatively thick walls of the retorts have been satisfactory.

The object of my invention is to heatsuch retorts and their contents in an even manner so as to avoid the disadvantages above referred to.

My invention comprises in general an improvement in heating retorts and their contents in which a retort of any desired,

shape, such as a spherical, cylindrical or other shape, is provided with means for heating the retort indirectly, by the use of a jacket rovided with a circulating current of a high-boiling liquid, as for example, oil. By; means of my invention a better regulation of the temperature used in the distillation can be obtained which results in a better yield of nitric acid because of the smaller amount of loss due to fumes produced by sudden changes in pressures. Furthermore, a purer and stronger acid is obtained because local overheating and' consequent decomposition are avoidedii Aga n, by means of my invenas for example,

tion, there is a great saving in expense, as the cracking of expensive retorts is avoided thereby enabling a saving to be made in installation and repairs,--as there is a saving in the amount of fuel used owing to the fact that my process is a more efiicient method for heating retorts, and asthere is much less labor required in order to operate my process. Furthermore, my process is more sanitary inasmuch as when the retorts crack poisonous fumes escape.

While my inventionis capable of embodiment in many different forms, pose of illustration, I haveshown one type of apparatus which may be used in carrying out my invention, in which the figure is a diagrammatic representation. of an elevation of an apparatus adapted to be used in accordance with my invention.

In the drawings, I have shown are tort l of any suitable material as for example cast iron, having an exit pipe 2. The retort 1 is Patented Ma 2.5, 1915.

for the pursurrounded with a jacket 3. An inlet pipe lconnectsWith the upper portion of said jacket, said pipe-havlng' a valve 5. .The

pipe 4 communicates with a supply pipe'6 leading from a pump 7 of any desired construction. From the pump 7 a pipe 8 communicates with an outlet pipe 9, having a valve 10, leading from an oil heater 11, con- 7 structed and heated in any suitable manner.

Oil from the circulating system is fed into, the heater 11 from a pipe 12, which communicates with a pipe 13, having a valve 14, The pipe 12 also communicateswith an expansion reservoir 15 by means of apip'e 16, the expansion reservoir 15 being open to the outer air; It will be noted that the expension reservoir 15 is located above the highest point of the circulatingsystem, so as to prevent the overflow of oil. As indicated in the drawings a pipe 13 communicates with the lower portion of the jacket 3 and communicates by means of a by-pass pipe 16, having a valve 17, with the point of union of the pipes 4 and 6. Another pipe 18, having a valve 18, leads from the pipe 13 to a cold oil tank 19. This cold oil tank 19 has'an outlet pipe 20 provided with a valve 21 to permit the oil' to be drawn on? when desired, and from the pipe 20 there is a pipe 22, which has a valve 23, and communicates with the two pipes 8 and 9 where the same are joined together. The parts conveying heated oil ane preferably covered with lagging 21.

In the operation of my process, when; the same is carried out-"in'connection with the apparatus previously} described, it will be assumed that the current of oil such as mineral oil, as for example, an oil of high flash point, is to be put in circulation for the purpose of heating the retort 1. The valves 17 and 23 Will then be closed While the remaining valves, except valve 21, will be in open position. When the pump 7 is thrown into operation a current of oil drawn from the heater 11 will be forced through pipes 9, 8, (3 and 4 into the jacket 3 from which the current of oil'will be forced through the pipes 13 and 12 back into the heater 11. By I this means a circulating current of oil is produced which heats the retort evenly through-- out; The temperature of the retort may be readily varied by controlling the temperature of the oil in the jacket 3 through the operation of valves 17 and 5, owing to the variation in the quantity ofthe heated oil supplied to the jacket. If at any time the retort becomes overheated for any reason, the oil heater 11 may be entirely disconnected from the system and a body of cold oil may be circulated through the jacket 3 by closing the valves 17, 10 and 14, and opening the remaining valves, except valve 21.

' When the retort has again reached the desired --temperature the valves can again be operated so as to circulate a current of heated oil through the jacket 3 in the manner already described. If at any time it is desired to draw oil the oil from the tank- 19 and from the circulating system including the jacket 3, the valve 21 may be opened for this purpose.

While I have described my invention above iii-detail, I wish it to be understood that many changes may be made therein without departing from the spirit of my invcntion; tl or instance, instead of heating or I cooling the retort by means of liquid in the outer acket such liquid 'may be contained withinv coils located inside the retort or outside the retort and inside the jacket, or both the jacket and such coils may he used.

l claim: y

l. The process which comprises distilling nitric acid by heating a still containing nitric acid by a hcatcdliquid circulatcdin a wloscd circle by aucxtraneous torcc.

2. he process which comprises distilling nitric acid by heatin z' a still containing nitric acid by a circulated heated liquid, and

nitricacid by heating a still containing nitric acid by al'heated liquid circulated in ,a closed circle by an extraneous force, and controlling the temperature of said still by vainto contact with the still.

a. The process which comprises distilling nitric acid by heating a still containing nitric acid by a circulated heated liquid controlling the temperature of said still by heating the liquid, and varying the quantity and temperature 01 the liquid brought into contact with the still.

5. The process which comprises distilling nitric acid by heating a still containing nitric acid by a heated oil circulated in' a closed circle by an extraneous force.

(l. The process which comprises distilling nitric acid by heating. a still containing nitric acid by a heated oil circulated in a closed circle by an extraneous force, and controlling the temperature of said still thereby. v A

7. The process which comprises distilling nitric acid by heating a still containing nitric acid by a heated oil circulated in a closed circle by an extraneous force, and controlling the temperature of said still by heating the oil.

8. The 1)1'()CGSS \\'l1lCll comprises distilling nitric acid by heating a still containing nitric acid by a circulated heated oil, and controlling the. temperature of said still by varying the quantity of oil brought into contact with the still.

9. The process which comprises distilling nitric acid by heating a still containing nitric acid by a heated oil circulated in a elbsed circle by an extraneous force, and controlling the temperature of said still by varying the temperature of the oil brought into contact with the still. i

10. The process which comprises distilling nitric acid by heating a still containing nitric acid by a heated oil, controlling the temperature of said still by heating the oil, and varying the quantity and temperature of the oil brought into contact with the still.

Tn testimony that I claim the foregoing l have hereunto set my hand.

Witnesses:

Dwion'r S. RonINsoN,

PM] I. K/nscn rying the temperature of the liquid brought 

